Due to increasing demands for data storage and data processing, new approaches have been proposed using networks comprising, for example, memory nodes and/or processing nodes to distribute the processing and storage of data across the nodes in the network. In some cases, networks have been proposed that include optical connections among some or all of the nodes to improve bandwidth among the nodes. However, in such cases, the routing of optical signals among the nodes involves converting the optical signals into electrical signals for processing before sending the optical signal back out to the next node toward the optical signal's intended final location.
In addition, the nodes themselves have conventionally included Printed Circuit Board Assemblies (PCBAs) with copper traces among the components within the node, such as a memory chip and a network interface on the PCBA. Although use of the latest PCBA techniques may be sufficient for current data processing needs, future systems will need faster connections among the components in the node with greater bandwidth. PCBA dielectric is also generally lossy at the high speeds desired for emergent data processing systems. Although the addition of more copper traces or lanes on the PCBA can provide greater bandwidth, this approach is limited by space on the PCBA.
A recent approach in the miniaturization of electronics has been the use of Multi-Chip Modules (MCMs) where multiple Integrated Circuits (ICs), semiconductor dies, and/or other components are integrated on a substrate. For example, in the case of Dynamic Random Access Memories (DRAMs), an MCM has been proposed as a High Bandwidth Memory (HBM) with DRAM dies stacked vertically to reduce the footprint of the MCM and a silicon interposer for connection to a substrate.